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Multi-stream signals separation based on space-time-isomeric (SPATIO) array using metasurface antennas

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Science China(Information Sciences) 2024年第2期67卷 181-200页

作者： Yangming LOU Liang JIN Huiming WANG Zhou ZHONG Junyan dai PLA Strategic Support Force Information Engineering University School of Information and Communications Engineering Xi'an Jiaotong University 3. State Key Laboratory of Millimeter WavesSoutheast University

In spatial domain signal processing, it is necessary to equip more antennas at the receiver to improve spatial demultiplexing capability. However, increasing the number of antennas under restricted space will reduce antenna spacing and raise the channel correlation, making the number of signal streams spatially demultiplexed much smaller than that of antennas. This paper proposes a method to design a space-timeisomeric(SPATIO) array based on metasurface antennas under wireless multipath conditions. Each antenna in this array has a different pattern and varies independently with time, reducing the channel correlation by superposing multipath at distinct positions and moments. Based on the SPATIO array, we present an array parameter design scheme based on infinity norm minimization, which can maximize the received energy of each stream while separating multi-stream received signals. Simulation results illustrate the performance of the SPATIO array for multi-stream signal reception. Compared with conventional multiple-input multipleoutput arrays, the proposed array can reduce the bit error rate by one order of magnitude under the same simulation conditions.

关键词： multiple-input multiple-output metasurface antenna space-time-isomeric array multipath channel degree of freedom

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生物质材料对微纳塑料吸附性能的研究进展

复合材料学报 2023年第2期40卷 637-648页

作者：朱高坚陈李栋段晟吴伟兵戴红旗卞辉洋南京林业大学轻工与食品学院南京210037

废弃塑料在江河湖海中呈累积趋势,老化分解产生的微纳塑料严重污染水质,威胁生态环境和居民饮用水安全。传统处理方法,如物理絮凝、生物降解等,存在处理周期长、吸附效率低等问题。天然生物质含有大量的羟基、羧基等活性基团,对生物质... 详细信息

废弃塑料在江河湖海中呈累积趋势,老化分解产生的微纳塑料严重污染水质,威胁生态环境和居民饮用水安全。传统处理方法,如物理絮凝、生物降解等,存在处理周期长、吸附效率低等问题。天然生物质含有大量的羟基、羧基等活性基团,对生物质进行物理处理或化学修饰改性能够改善孔隙结构和提高比表面积,可作为吸附微纳塑料的绿色材料。本文从微纳塑料的常规处理方法和基本特征出发,简要概况了不同类型微纳塑料对植物、动物和人体的潜在影响和危害,系统介绍了生物质材料(生物质炭、纤维素、甲壳素等)在微纳塑料吸附领域的研究现状,分析总结了生物质材料对微纳塑料的吸附行为、规律和作用机制,最后展望了生物质材料吸附微纳塑料的未来发展前景。

关键词：生物质吸附材料微纳塑料吸附性能吸附机制

微晶纤维素ARGET ATRP接枝共聚制备PMMA和PMAA-Na的研究

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南京林业大学学报（自然科学版） 2014年第1期38卷 125-129页

作者：庄志良吴伟兵谷军戴红旗南京林业大学江苏省制浆造纸科学与技术重点实验室江苏南京210037

使用再生电子转移生成催化剂原子转移自由基聚合(ARGET ATRP)方法,在微晶纤维素表面分别接枝了甲基丙烯酸甲酯(MMA)和甲基丙烯酸钠(MAA-Na),FT-IR图谱和SEM照片证明纤维素基表面成功接枝聚甲基丙烯酸甲酯(PMMA);凝胶渗透色谱分析表明PMM... 详细信息

使用再生电子转移生成催化剂原子转移自由基聚合(ARGET ATRP)方法,在微晶纤维素表面分别接枝了甲基丙烯酸甲酯(MMA)和甲基丙烯酸钠(MAA-Na),FT-IR图谱和SEM照片证明纤维素基表面成功接枝聚甲基丙烯酸甲酯(PMMA);凝胶渗透色谱分析表明PMMA的分子质量分布较窄,M w/M n=1.12,说明ARGET ATRP实现了对接枝侧链分布均一性的有效控制。MAA-Na单体的转化率随反应时间的增加而增加,可在接枝侧链分布均一性的基础上通过调整反应时间实现侧链长度的有效可控。ARGET ATRP可实现对微晶纤维素表面接枝侧链分布和长度的控制。

关键词： ARGET ATRP 微晶纤维素可控聚合分子质量分布

Catalytic upgrading biomass-derived ethanol and acetic acid into C4 chemicals

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Science China Chemistry 2024年第11期67卷 3588-3613页

作者： Tingting Yan Mengting Zhang Runzhi Yuan Weili dai College of Science Civil Aviation University of China School of Materials Science and Engineering & National Institute for Advanced Materials Nankai University

Synthesis of value-added chemicals from biomass is an essential strategy to mitigate the global dependency on fossil resources and achieve the aim of carbon neutrality. Thereinto, ethanol and acetic acid are crucial biomass-derived platform ***, catalytic upgrading ethanol and acetic acid into C4 energy-intensive fuels and chemicals via the elongation of carbon backbone has received widespread attention. The primary focus of this review is to systematically describe the recent breakthrough in the conversion of ethanol or acetic acid to C4 chemicals including 1,3-butadiene, n-butenes, isobutene or *** attentions will be given to heterogeneous catalyst design strategies, reaction parameters on the catalytic performance along with the relevant mechanism investigations, as well as their future challenges and opportunities. The present review will provide the detailed insights into the synthesis of C4 chemicals from biomass-derived ethanol and acetic acid and shed a light on the development of highly efficient catalysts.

关键词： ethanol acetic acid C4 chemicals catalytic upgrading aldol condensation

Extracorporeal membrane oxygenation as a bridging therapy for patients with thiamine deficiency-induced pulmonary arterial hypertension

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World Journal of Emergency Medicine 2024年第2期15卷 147-149页

作者： Fangfang Qiu Weixing dai Tengyue Huang Min Li Department of Intensive Care Unit the Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Department of Intensive Care Unit the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China

Thiamine deficiency is characterized by a deficiency of thiamine(vitamin B1),lactic acidosis,pulmonary arterial hypertension(PAH),right-sided heart failure,and peripheral nerve *** deficiency is easily misdiagnosed and missed during clinical practice and is associated with death in severe cases.[1,2]Here we reported a patient who was admitted to the hospital with severe metabolic acidosis and pulmonary hypertension and finally diagnosed with thiamine deficiency by detecting plasma vitamin B1 *** clinically obvious thiamine deficiency is rare,and cases of thiamine deficiency requiring extracorporeal membrane oxygenation(ECMO)treatment are rarer,we believe that our case will be helpful for emergency clinicians.

关键词： vitamin hypertension arterial

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese Chemical Letters 2024年第6期35卷 451-455页

作者： Kebo Xie Qian Zhang Fei Ye Jungui dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2-6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2(SGLT2)inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2 inhibitory activity

Fault Analysis on AES:A Property-Based Verification Perspective

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Tsinghua Science and Technology 2024年第2期29卷 576-588页

作者： Xiaojie dai Xingxin Wang Xue Qu Baolei Mao Wei Hu School of Cybersecurity Northwestern Polytechnical UniversityXi’an 710072China School of Cyber Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Fault analysis is a frequently used side-channel attack for ***,existing fault attack methods usually involve complex fault fusion analysis or computation-intensive statistical analysis of massive fault *** this work,we take a property-based formal verification approach to fault *** derive fine-grained formal models for automatic fault propagation and fusion,which establish a mathematical foundation for precise measurement and formal reasoning of fault *** extract the correlations in fault effects in order to create properties for fault *** further propose a method for key recovery,by formally checking when the extracted properties can be satisfied with partial keys as the search *** results using both unprotected and masked advanced encryption standard(AES)implementations show that our method has a key search complexity of 216,which only requires two correct and faulty ciphertext pairs to determine the secret key,and does not assume knowledge about fault location or pattern.

关键词： side-channel attack fault analysis fault propagation model property extraction fault verification

Editorial:special topic on heterojunction in photocatalysts

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Science China Materials 2024年第2期67卷 379-381页

作者： Jiaguo Yu Xin Li Junwei Fu Kai dai Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China Hunan Joint International Research Center for Carbon Dioxide Resource Utilization State Key Laboratory of Powder MetallurgySchool of PhysicsCentral South UniversityChangsha 410083China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation College of Physics and Electronic InformationHuaibei Normal UniversityHuaibei 235000China

To suppress the recombination of photogenerated electron and hole in single photocatalysts,an important method is to design heterojunction by combining two *** method has widely used to enhance the photocatalytic performance of the *** the begining,most people use type-Ⅱcharge carrier transfer mechanism to explain the emhanced activity of the composite semiconductors.

关键词： composite heterojunction method

Eco-friendly regeneration of end-of-life PVDF membrane with triethyl phosphate:Efficiency and mechanism

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Chinese Chemical Letters 2024年第9期35卷 315-319页

作者： Lingna Wang Chenxin Tian Ruobin dai Zhiwei Wang State Key Laboratory of Pollution Control and Resource Reuse Shanghai Institute of Pollution Control and Ecological SecuritySchool of Environmental Science and EngineeringTongji UniversityShanghai 200092China

Membrane will inevitably reach the end of its lifespan due to the irrecoverable fouling accumulation in membrane bioreactors(MBRs)during long-term ***,we developed an eco-friendly membrane regeneration strategy with triethyl phosphate(TEP),which successfully prolonged the lifespan of end-of-life(EOL)polyvinylidene fluoride(PVDF)membranes in a large-scale *** regenerated(Rg)membrane exhibited a water permeance of 534.8±45.7 L m^(-2)h^(-1)bar-1,along with stable rejection rate,which was comparable with that of the new ***,compared to the membrane subjected solely to preliminary cleaning,the Rg membrane presented a more hydrophilic surface due to the combination of preliminary cleaning and solvent-based ***,the Rg membrane presented less fouling propensity with the critical flux of 15.2 L m^(-2)h^(-1),significantly higher than that of the EOL membrane(4.0 L m^(-2)h^(-1)).Importantly,the membrane regeneration strategy was capable of guaranteeing the effluent quality in MBR systems for treating real municipal *** study provides an eco-friendly membrane regeneration strategy for effectively removing the irrecoverable foulants,thereby promoting the advancement of sustainable membrane-based wastewater treatment technology.

关键词： End-of-life membrane regeneration Membrane bioreactor Preliminary cleaning Solvent-based processing Irrecoverable fouling removal